WO2020162090A1

WO2020162090A1 - Dental therapy device and method for driving same

Info

Publication number: WO2020162090A1
Application number: PCT/JP2020/000297
Authority: WO
Inventors: 恭平加藤; 的場　一成
Original assignee: 株式会社モリタ製作所
Priority date: 2019-02-06
Filing date: 2020-01-08
Publication date: 2020-08-13
Also published as: EP3922206B1; EP3922206A4; JP2020124408A; EP3922206A1; JP7032340B2; CN113395946A; US20220087777A1; CN113395946B

Abstract

This dental therapy device comprises: a drive unit that is structured from a micro motor (7) and a motor driver (13), or similar; a control unit (11); and a root canal length measurement circuit (12). The control unit (11) forward-rotationally drives a cutting tool (5), which is retained in a head unit (2), in a direction in which the same cuts a cutting target. When the cutting tool (5) is forward-rotationally driven and the root canal length measurement circuit (12) detects the arrival of a tip of the cutting tool (5) at a reference location, the control unit (11) reverse-rotationally drives the cutting tool (5) in the opposite direction from the forward-rotational driving. When the cutting tool (5) is reverse-rotationally driven and the root canal length measurement circuit (12) detects movement of the tip of the cutting tool (5) in the direction of a root tip location, the control unit (11) performs failsafe control.

Description

Dental treatment apparatus and driving method thereof

The present invention relates to a dental treatment device provided with a handpiece, and more particularly to a dental treatment device for cutting and enlarging an inner wall of a tooth root canal (hereinafter also simply referred to as a root canal) and a driving method thereof.

In dental treatment, treatment to cut and enlarge the root canal may be performed. For the treatment, a dental treatment device in which a cutting tool called a file or a reamer is attached to the head portion of the handpiece is used, and the root canal is cut and enlarged by driving the cutting tool. When the dental treatment device drives the cutting tool to cut and expand the root canal, the blade of the cutting tool bites into the root canal wall, and the cutting tool is constrained at this biting part The cutting tool was sometimes twisted and broken when rotated.

In the dental treatment device disclosed in Patent Document 1, in order to prevent the cutting tool from breaking, the rotation direction of the motor reverses at regular time intervals, and the cutting tool performs normal rotation and reverse rotation at regular time intervals. A handpiece that performs a twist drive of a forward/reverse rotation operation that is repeated is disclosed.

International Publication No. 2012/164875

The cutting tool can cut the root canal when driven in the clockwise direction, but cannot cut the root canal when driven in the counterclockwise direction or reduces the cutting efficiency. A tool and a second cutting tool capable of cutting the root canal when driven in the counterclockwise direction but not capable of cutting the root canal when driven in the clockwise direction or having a reduced cutting efficiency; There is.

In the dental treatment device disclosed in Patent Document 1, when the first cutting tool is attached to the head part, the first cutting tool is driven by a twist drive in which the rotation angle in the clockwise direction is larger than the rotation angle in the counterclockwise direction. Can efficiently cut the root canal. On the other hand, in the dental treatment device, when the second cutting tool is attached to the head portion, the rotation angle in the counterclockwise direction is made larger than the rotation angle in the clockwise direction and twist driving is performed to efficiently drive the root canal. It can be cut.

However, in the dental treatment apparatus, if the first cutting tool is intended to be attached to the head part but the second cutting tool is mistakenly attached, an operation different from the drive operated by the user will be executed. Especially, in the dental treatment device including the root canal length measurement circuit, when the tip of the cutting tool reaches the root apex position, it is driven by twist drive that makes the rotation angle in the clockwise direction larger than the rotation angle in the counterclockwise direction. Control is performed to switch the drive that has been performed to the drive in the counterclockwise direction. At this time, if the cutting tool attached to the head portion is incorrect, an unintended operation (abnormal operation) occurs.

The present invention has been made to solve the above problems, and provides a dental treatment apparatus and a driving method thereof that can be safely driven even if the cutting tool attached to the head portion is incorrect. With the goal.

The dental treatment apparatus according to the present invention is obtained by a drive unit that drives the cutting tool held in the head portion of the handpiece, a control unit that controls the drive unit that drives the cutting tool, and an electrical root canal length measurement. The controller has a position detector that detects the position of the tip of the cutting tool in the root canal, and the controller drives the cutting tool held in the head part in the normal direction to cut the object to be cut, and drives the cutting tool forward. When the position detection unit detects the arrival of the tip of the cutting tool at the reference position by rolling drive, the cutting tool is reversely driven in the reverse direction of the normal rotation drive, the cutting tool is reversely driven, and the position detection unit When detecting the movement of the tip of the cutting tool in the direction of the apex position, fail-safe control is executed.

Another dental treatment apparatus according to the present invention detects a load applied to a cutting tool, a drive section that drives a cutting tool held in a head section of a handpiece, a control section that controls the driving section that drives the cutting tool, and a driving section. And a load detection unit that controls the control unit to drive the cutting tool held in the head portion in the normal direction to cut the object to be cut, drive the cutting tool in the forward direction, and detect the load detection unit in the cutting tool. If the load applied to the cutting tool is equal to or greater than the reference load, the cutting tool is reversely driven in the reverse direction of the normal rotation drive, and the cutting tool is reversely driven so that the load applied to the cutting tool detected by the load detection unit does not fall below the reference load. If so, execute fail-safe control.

A method of driving a dental treatment apparatus according to the present invention includes a drive unit that drives a cutting tool held by a head portion of a handpiece, a control unit that controls the drive unit that drives the cutting tool, and an electrical root canal length. A method for driving a dental treatment device comprising a position detection unit that detects a position of a tip of a cutting tool obtained by measurement in a root canal, wherein the control unit is a cutting object held by a cutting tool. When driving the cutting tool in the forward direction and the position detector detects the arrival of the tip of the cutting tool at the reference position, the cutting tool is driven in the reverse direction The method includes the step of driving in reverse, and the step of performing fail-safe control when the cutting tool is driven in reverse and the position detector detects movement of the tip of the cutting tool in the direction of the apex position.

Since the dental treatment apparatus according to the present invention executes fail-safe control even when the cutting tool is driven in reverse to cause an unintended operation, it can be safely driven even if the cutting tool attached to the head is wrong. You can

1 is a schematic diagram showing the configuration of a root canal treating device according to the first embodiment. 4 is a block diagram showing a functional configuration of a root canal treating device according to the first embodiment. FIG. It is a circuit diagram which shows the circuit structure of the root canal treatment device which concerns on this Embodiment 1. It is a schematic diagram which showed the rotating direction of the cutting tool. FIG. 4 is a block diagram for explaining a control flow in a control unit of the root canal treating device according to the first embodiment. 7 is a flowchart for explaining two-step control executed in the root canal treating device according to the first embodiment. FIG. 5 is a schematic diagram for explaining two-step control executed in the root canal treating device according to the first embodiment. FIG. 5 is a schematic diagram for explaining a first reference position and a second reference position set in the root canal treating device according to the first embodiment. 7 is a flowchart for explaining two-step control executed in the root canal treating device according to the second embodiment. It is the schematic which shows the structure of the root canal treatment device connected with the control box provided in the exterior of the handpiece with the cord.

(Overview)
The treatment of cutting and enlarging the root canal is a very difficult treatment because the degree to which the root canal is curved and the condition in which the root canal is calcified and blocked depending on the person. When cutting and enlarging the root canal using a root canal treatment device that is a dental treatment device, it is necessary to cut and expand the root canal from the root canal opening to the apex position, but beyond the apex position. Techniques for preventing cutting and enlarging are known.

Specifically, when the root canal treatment device determines that the tip of the cutting tool has reached the apex position using the root canal length measurement circuit, it switches the driving of the cutting tool from forward rotation drive to reverse rotation drive, Prevents cutting and enlarging beyond the pointed position. Here, the normal rotation drive is drive in the direction of cutting the root canal wall that is the object to be cut, and is the clockwise drive in the case of the first cutting tool. The reverse rotation drive is a reverse drive of the normal rotation drive, and is a counterclockwise drive in the case of the first cutting tool. Since the first cutting tool has the blade formed so as to perform cutting by driving in the clockwise direction, when the driving in the clockwise direction is driven as the forward rotation drive, the screw approaches the root apex position as if to bite. The tip of the cutting tool advances in the direction. On the contrary, when the first cutting tool is driven in the counterclockwise direction as reverse driving, the tip of the cutting tool advances in a direction away from the apex position so as to loosen the screw.

However, the cutting tools that can be attached to the head portion of the root canal treatment device perform the cutting in the counterclockwise direction in addition to the first cutting tool in which the blade is formed so as to perform the cutting in the clockwise direction. There is a second cutting tool having a blade formed therein. Since the second cutting tool has the blade formed so as to perform cutting by driving in the counterclockwise direction, when the driving in the counterclockwise direction is driven as forward rotation driving, the tip of the cutting tool approaches the apex position. Advances. On the contrary, in the second cutting tool, when the clockwise driving is driven as the reverse driving, the tip of the cutting tool advances in the direction away from the apex position. Therefore, when the second cutting tool is attached with the intention that the first cutting tool is attached to the head portion of the root canal treating device, the operation is not intended by the user (abnormal operation). In other words, if the tip of the cutting tool determines that the tip of the cutting tool has reached the apex position and drives the cutting tool with the reverse rotation drive, the tip of the cutting tool does not move away from the apex position but rather the apex of the apex. The operation further proceeds in the direction of the position, and the operation is not intended by the user.

Therefore, in the root canal treatment device described in this specification, when it is determined that the tip of the cutting tool has reached the apex position and the cutting tool is driven by the reverse rotation drive, the operation of further advancing toward the apex position is performed. If it is performed, two-step control is performed to determine that the operation is abnormal and stop the driving. When the first cutting tool is attached with the intention that the second cutting tool is attached to the head portion of the root canal treating device, the relationship between the driving direction of the root canal treating device and the normal rotation driving and the reverse rotation driving is reversed. Becomes

In addition, in the root canal treatment device, the cutting tool can be driven not only by simple forward drive and reverse drive, but also by twist drive that combines forward drive and reverse drive. When the first cutting tool is driven by twisting, the root canal treating device can efficiently cut the root canal by driving the first cutting tool by twist driving in which the rotation angle in the clockwise direction is larger than the rotation angle in the counterclockwise direction. it can. Further, in the root canal treating device, when the second cutting tool is driven by twisting, the root canal is efficiently cut by driving with a twist drive in which the rotation angle in the counterclockwise direction is larger than the rotation angle in the clockwise direction. be able to. When the cutting tool is driven by twist drive, the driving in the clockwise direction and the drive in the counterclockwise direction are always included, so the user should make sure that the wrong cutting tool is attached to the head part of the root canal treating device. Is hard to notice.

In the present specification, driving including clockwise driving and twist driving in which the rotation angle of clockwise driving is larger than the rotation angle of counterclockwise driving is mainly referred to as clockwise driving, The drive including the counterclockwise drive and the twist drive in which the rotation angle of the counterclockwise drive is larger than the rotation angle of the clockwise drive is mainly referred to as counterclockwise drive. Further, when the first cutting tool is driven in the clockwise direction, it is driven in the normal direction, when the first cutting tool is driven in the counterclockwise direction, it is driven in the reverse direction, and when the second cutting tool is driven in the counterclockwise direction, it is driven in the normal direction. When the cutting tool is driven clockwise, it is called reverse rotation drive.

As described above, in the root canal treatment device described in the present specification, the control from the normal rotation drive to the reverse rotation drive performed when the tip of the cutting tool reaches the root apex position and the error of the cutting tool attached to the head part are performed. With regard to the two-step control including the fail safe control for preventing the abnormal operation from occurring when the reverse rotation control is performed by the following, specific embodiments will be described in detail below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic diagram showing the configuration of a root canal treating device 100 according to the first embodiment. FIG. 2 is a block diagram showing a functional configuration of the root canal treating device according to the first embodiment. The dental treatment device according to the first embodiment will be described as a root canal treating device 100 including a handpiece 1 for dental root canal treatment, including a system such as root canal expansion and root canal length measurement. However, the dental treatment device according to the present invention is not limited to the root canal treating device 100, and can be applied to a dental treatment device having a similar configuration.

The root canal treating device 100 shown in FIG. 1 includes a handpiece 1, a motor unit 6, and a control box 9 for dental root canal treatment inside the handpiece 1. That is, the root canal treating device 100 shown in FIG. 1 is a cordless type root canal treating device, not the configuration in which the handpiece 1 is connected to the control box via the hose.

A handpiece 1 for dental root canal treatment includes a head portion 2, a neck portion 3 having a small diameter connected to the head portion 2, and a grip portion 4 connected to the neck portion 3 and gripped by a finger. There is. The grip unit 4 has a motor unit 6 and a control box 9 for rotating the cutting tool 5 (file or reamer) held by the head unit 2 therein.

The motor unit 6 has a built-in micromotor 7 as shown in FIG. 2, a power supply lead wire 71 for supplying power to the micromotor 7, and a signal for transmitting a signal to a root canal length measuring circuit 12 described later. It is connected to the control box 9 via a lead wire 8 and the like. Here, the signal lead wire 8 is a part of a conductor that is electrically connected to the cutting tool 5 through the motor unit 6 and the handpiece 1 and transmits an electric signal. The cutting tool 5 serves as one electrode of the root canal length measuring circuit 12.

The control box 9 includes a control unit 11, a comparison circuit 110, a root canal length measurement circuit 12, a motor driver 13, a setting unit 14, an operation unit 15, a display unit 16 and a notification unit 17. Although not shown in FIG. 1, the lead wire 19 may be led out from the grip portion 4, for example. One of the lead wires 19 is connected to the root canal length measuring circuit 12, and the other end of the lead wire 19 is attached with an oral electrode 19a to be hung on the lips of the patient in an electrically conductive state. The oral cavity electrode 19a serves as the other electrode of the root canal length measuring circuit 12.

The control unit 11 controls the entire root canal lengthening and root canal length measuring system, and its main part is composed of a microcomputer. The control unit 11 is connected with a comparison circuit 110, a root canal length measuring circuit 12, a motor driver 13, a setting unit 14, an operation unit 15, a display unit 16, and an informing unit 17. The control unit 11 controls the rotation direction of the cutting tool 5 that cuts the object to be cut. Specifically, the control unit 11 drives the cutting tool 5 in a clockwise direction (also referred to as a clockwise direction) and rotates the cutting tool 5 in a counterclockwise (also referred to as a counterclockwise) direction in accordance with a drive sequence. Either of the counterclockwise drive controls is performed. Here, the turning direction of the cutting tool (clockwise direction or counterclockwise direction) is considered based on the case where the tip direction of the cutting tool 5 faces from the side of the cutting tool 5 attached to the head portion 2. Further, the control unit 11 changes each parameter of the clockwise rotation angle, the rotation speed, or the rotation angular velocity (rotation speed), the counterclockwise rotation angle, the rotation speed or the rotation angular velocity (rotation speed), and the number of repetitions. Then, the drive control for rotating the cutting tool 5 can be performed.

Here, the rotation angle is a rotation amount that represents the size of turning the cutting tool 5 in the clockwise direction or the counterclockwise direction, and the rotation time (driving period when the number of rotations and the rotational angular velocity (rotation number) are constant. Also referred to as). Further, the rotation angle may be defined by an amount related to the driving of the cutting tool 5, such as a driving current amount or a torque amount. Strictly speaking, depending on the load applied to the cutting tool and the motor, for example, the correspondence between the rotation time for control and the actual rotation angle may have to be corrected, but the correction amount is extremely small and ignored in the practice of the present invention. can do.

The comparison circuit 110 is a configuration necessary to detect the load applied to the cutting tool 5, and can be selectively provided when the load needs to be detected. The comparison circuit 110 can compare the loads at any time when the motor driver 13 rotates the cutting tool 5 in the clockwise direction or the counterclockwise direction. Specifically, the comparison circuit 110 compares the load applied to the cutting tool 5 with the reference load after rotating the cutting tool 5 in the clockwise direction or the counterclockwise direction by a predetermined rotation angle (for example, 180 degrees). You can

The root canal length measuring circuit 12 is a structure necessary for detecting the position of the tip of the cutting tool 5 in the root canal, and can be selectively provided when the position needs to be detected. is there. The root canal length measuring circuit 12 constitutes a closed circuit using the cutting tool 5 inserted into the root canal as one electrode and the oral cavity electrode 19a hung on the lips of the patient as the other electrode. Then, the root canal length measuring circuit 12 applies a measurement voltage between the cutting tool 5 and the oral cavity electrode 19a and measures the impedance between the cutting tool 5 and the oral cavity electrode 19a to determine the apex position of the tooth. The distance from to the tip of the cutting tool 5 can be measured. When the root canal length measuring circuit 12 detects that the tip of the cutting tool 5 has reached the root apex position, the insertion amount of the cutting tool, that is, the distance from the root canal to the tip of the cutting tool is set as the root canal length. You can The electrical root canal length measuring method for measuring the root canal length by measuring the impedance between the cutting tool 5 and the oral cavity electrode 19a is a known method, and the root canal treating device 100 according to the first embodiment. For this, all known methods for measuring the electric root canal length can be applied.

The motor driver 13 is connected to the micromotor 7 via a power supply lead wire 71, and controls the power supplied to the micromotor 7 based on a control signal from the control unit 11. The motor driver 13 controls the power supply to the micromotor 7 to control the rotation direction, the rotation speed and the rotation angle of the micromotor 7, that is, the rotation direction, the rotation speed and the rotation angle of the cutting tool 5. You can The driving unit is mainly composed of the micromotor 7 and the motor driver 13.

The setting unit 14 has a selection button 15b (see FIG. 1) for changing the setting on the surface of the gripping unit 4, and by operating the selection button 15b, the rotation direction, rotation speed, and rotation of the cutting tool 5 can be obtained. Set the standard to control the angle. Further, the setting unit 14 can set parameters such as the rotation speed and the rotation angle of the cutting tool 5, as well as setting whether or not to perform root canal length measurement. Further, the setting unit 14 sets a switching reference (a reference for switching a drive sequence or a parameter of a drive pattern), a reference load, a timing and the like to be compared with the load applied to the cutting tool 5 in the comparison circuit 110.

The operation portion 15 has a drive start/stop button 15a (see FIG. 1) on the surface of the grip portion 4, and the drive of the cutting tool 5 is started or stopped by operating the drive start/stop button 15a. be able to. That is, when the drive start/stop button 15 a is operated while the driving of the cutting tool 5 is stopped, the operation unit 15 transmits an instruction signal to start the driving of the cutting tool 5 to the control unit 11. When the drive start/stop button 15a is operated while the cutting tool 5 is being driven, the operation unit 15 sends an instruction signal for stopping the driving of the cutting tool 5 to the control unit 11. Here, the driving of the cutting tool 5 refers to a period from when the driving of the cutting tool 5 is started by the operation of the driving start/stop button 15a to when the driving is stopped. Therefore, when the detected load exceeds the reference load and the drive of the cutting tool 5 is forcibly stopped, the drive of the cutting tool 5 is not stopped by the operation of the drive start/stop button 15a. 5 is included during driving.

The display unit 16 displays the position of the tip of the cutting tool 5 in the root canal, the rotation direction of the cutting tool 5, the rotation speed, the rotation angle, and the like. Furthermore, the information for the notification unit 17 to notify the user can be displayed on the display unit 16. In the cordless type root canal treating device 100, the grasping part 4 is provided with the display part 16. Therefore, the user is driving the cutting tool 5 in the cutting direction or in the non-cutting direction without greatly changing the line of sight, the current position of the cutting tool 5, and the cutting tool. It is possible to confirm information such as the load applied to 5 and the number of rotations.

The notification unit 17 notifies the drive state of the cutting tool 5 currently performed by the control unit 11 by light, sound, vibration, or the like. Specifically, the notification unit 17 is provided with an LED (Light Emitting Diode), a speaker, a vibrator, and the like as necessary to notify the driving state of the cutting tool 5, and drives clockwise and counterclockwise. Driving changes the color of the LED that emits light and the sound output from the speaker. If the display unit 16 can display the driving state of the cutting tool 5 to the user on the display unit 16, the notification unit 17 does not need to be separately provided with an LED, a speaker, a vibrator, or the like.

Next, the circuit configuration of the root canal treating device 100 that controls the driving of the cutting tool 5 will be described in more detail. FIG. 3 is a circuit diagram showing a circuit configuration of the root canal treating device 100 according to the first embodiment. In the root canal treating device 100 shown in FIG. 3, the parts of the micromotor 7, the control unit 11, the comparison circuit 110, the root canal length measuring circuit 12, the motor driver 13, and the setting unit 14 which are related to the drive control of the cutting tool 5. It is shown.

Further, the motor driver 13 includes a transistor switch 13a, a transistor driver circuit 13b, a rotation direction changeover switch 13c, and a load detection resistor 13d. The rotation direction change-over switch 13c is described as a relay element, but the motor drive circuit may be configured by a semiconductor switch element such as an FET. The setting unit 14 includes a variable resistor 14a for setting a reference load, a variable resistor 14b for setting a duty, and a variable resistor 14c for setting a reference position. The setting unit 14 also includes a configuration for setting a rotation angle (or a rotation time) indicating a timing at which the load detected by the comparison circuit 110 and the reference load are compared. The configuration is shown in FIG. Not shown. The root canal treating device 100 shown in FIG. 3 is connected to a main power source 20 and a main switch 21. Although not shown, the cutting tool 5 is held by the micromotor 7 via an appropriate gear mechanism or the like.

The transistor driver circuit 13b operates by a control signal output from the port 11a of the control unit 11, and controls the on/off of the transistor switch 13a to drive the micromotor 7. The micromotor 7 rotates clockwise or counterclockwise depending on the state of the rotation direction changeover switch 13c. When the control signal output from the port 11a of the control unit 11 has, for example, a pulse waveform repeated at a constant cycle, the width of the pulse waveform, that is, the duty ratio is adjusted by the variable resistor 14b for setting the duty of the setting unit 14. To be done. The micromotor 7 drives the cutting tool 5 at a rotation speed corresponding to this duty ratio.

The rotation direction changeover switch 13c is a control signal output from the port 11b of the control unit 11 and switches whether to drive the cutting tool 5 clockwise or counterclockwise. The control unit 11 detects the load applied to the cutting tool 5 based on the amount of current (or voltage value) of the load detection resistor 13d input to the port 11c. Therefore, the load detection resistor 13d functions as a load detection unit that detects the load applied to the cutting tool 5. The load detection unit is not limited to a configuration in which the load applied to the cutting tool 5 is detected based on the amount of current (or voltage value) of the load detection resistor 13d. For example, a torque is applied to the drive portion of the cutting tool 5. Another configuration such as a configuration in which a sensor is provided to detect the load applied to the cutting tool 5 may be used. The detected load is converted into a torque value applied to the cutting tool 5 by the control unit 11 and displayed on the display unit 16, for example. Further, the comparison circuit 110 compares the torque value converted by the control unit 11 with the torque value set by using the reference load setting variable resistor 14a. Of course, the comparison circuit 110 may be configured to directly compare the current amount (or voltage value) of the load detection resistor 13d and the current amount (or voltage value) of the variable resistor 14a without converting the torque value.

Further, the control unit 11 inputs the root canal length measured by the root canal length measuring circuit 12 into the port 11d. Therefore, the root canal length measuring circuit 12 functions as a position detector that detects the position of the tip of the cutting tool 5 in the root canal. Further, the control unit 11 outputs the load applied to the cutting tool 5 detected by the load detection unit from the port 11e to the comparison circuit 110, and the comparison result obtained by the comparison circuit 110 comparing with the reference load is input from the port 11e. Therefore, the comparison circuit 110 functions as a load comparison unit that compares the load detected by the load detection unit and the reference load. The control unit 11 may combine the configuration described in the analog circuit as software in one microcomputer.

FIG. 4 is a schematic diagram showing the rotation direction of the cutting tool 5. In the rotation direction of the cutting tool 5 shown in FIG. 4, driving in a clockwise direction 5a that turns the cutting tool 5 clockwise from the side of the cutting tool 5 attached to the head portion 2 toward the tip direction of the cutting tool 5 is performed. , Driving counterclockwise to rotate counterclockwise 5b is shown. In addition, the drive for rotating the cutting tool 5 in the clockwise direction 5a at the predetermined rotation angle and the drive for rotating the cutting tool 5 in the counterclockwise direction 5b at the predetermined rotation angle are alternately performed. , Twist drive. In the twist drive, alternate rotations in the clockwise direction and the counterclockwise direction may be performed with the same drive amount or may be performed with different drive amounts.

[Two-step control]
Next, the two-step control in the root canal treating device 100 according to the first embodiment will be described. FIG. 5 is a block diagram for explaining a control flow in the control unit 11 of the root canal treating device 100 according to the first embodiment. The control unit 11 has three controls, namely, a forward rotation control 111, a reverse rotation control 112, and a fail-safe control 113, as controls for driving the cutting tool 5. The forward rotation control 111 is control for driving the cutting tool 5 in the forward direction to cut and enlarge the root canal. That is, in the forward rotation control 111, for example, when the first cutting tool is attached to the head part 2, the cutting tool 5 is mainly controlled to be driven clockwise, and the second cutting tool is attached to the head part 2. In this case, the cutting tool 5 is mainly controlled to drive counterclockwise.

The control unit 11 causes the root canal length measuring circuit 12 to move the cutting tool 5 to the reference position (for example, the apex position) while driving the cutting tool 5 by the forward rotation control 111 to perform cutting and enlarging the root canal. When detecting the arrival of the leading edge of, the control shifts from the forward rotation control 111 to the reverse rotation control 112. The reverse rotation control 112 is a control that reverses the drive from the normal drive to the reverse drive. That is, for example, when the first cutting tool is attached to the head unit 2, the reverse rotation control 112 controls the driving of the cutting tool 5 mainly to the counterclockwise drive, and the second cutting tool is attached to the head unit 2. If the cutting tool 5 is driven, the driving of the cutting tool 5 is mainly controlled to be clockwise. The reference position may be, for example, a position preset by the user in the root canal other than being set at the apex position.

The tip of the cutting tool 5 advances in a direction approaching the root apex while cutting and enlarging the root canal by driving in the forward direction, and the tip of the cutting tool 5 advances in a direction away from the reference position when driven in the reverse direction. It will be. Therefore, the reverse rotation control 112 controls the drive in the direction away from the reference position by driving the cutting tool 5 in the reverse direction. When the root canal length measuring circuit 12 detects that the tip of the cutting tool 5 has not reached the reference position by driving the cutting tool 5 in the reverse direction, the control can be returned from the reverse control 112 to the forward control 111. it can.

However, if the cutting tool 5 attached to the head unit 2 is incorrect, even if the reverse rotation control 112 drives the cutting tool 5 in the reverse direction, the tip of the cutting tool 5 further advances toward the apex position. Therefore, when the root canal length measuring circuit 12 detects the movement of the tip of the cutting tool 5 in the direction of the root apex when the cutting tool 5 is reversely driven by the reverse rotation control 112, it is determined that an abnormal operation is detected, and the reverse rotation is detected. The control shifts from the control 112 to the fail-safe control 113.

The fail-safe control 113 is control for stopping driving of the cutting tool 5. Thereby, even if the cutting tool 5 attached to the head portion 2 is wrong, the root canal treating device 100 can prevent the cutting and enlarging beyond the apex position. The fail-safe control 113 is not limited to the control for stopping the driving of the cutting tool 5 even if the cutting tool 5 attached to the head unit 2 is erroneous as long as the driving in the reverse rotation control 112 can prevent the abnormal operation. The fail-safe control 113 outputs, for example, control for decreasing the rotational speed of the cutting tool 5, control for twist driving the cutting tool 5, control for reversing the driving direction of the cutting tool 5, control for outputting a sound, and light. At least one of the control and the control for vibrating the handpiece 1 may be included. Specifically, the fail-safe control 113 performs control for reversing the driving direction of the cutting tool 5 and sets the reverse rotation drive of the cutting tool 5 by the reverse rotation control 112 to the normal rotation drive, so that when the cutting tool 5 is incorrect. The abnormal operation of may be prevented. When the root canal length measuring circuit 12 detects the movement of the tip of the cutting tool 5 in the direction of the root apex, the fail-safe control 113 outputs a sound or light using the notification unit 17 to notify the abnormal operation. The control may be performed to prevent abnormal operation when the cutting tool 5 is erroneous.

When the drive of the cutting tool 5 is stopped by the fail-safe control 113, the control is continued until the release operation is performed. That is, a release operation is required to return from the fail-safe control 113 to the normal rotation control 111. The releasing operation is, for example, an operation in which the root canal length measuring circuit 12 detects that the tip of the cutting tool 5 has reached a predetermined position (for example, a root canal opening) that is closer to the crown than the reference position. Note that the release operation is not limited to this, and another operation such as long-pressing the drive start/stop button 15a may be set.

In the root canal treating device 100, when the cutting tool 5 is driven by the forward rotation control 111 as shown in FIG. 5, when the tip of the cutting tool 5 reaches the reference position, the driving is switched by the reverse rotation control 112. Two-step control is performed in which the first-step control is performed, and when the abnormal operation is detected, the second-step control is switched to the drive in the fail-safe control 113. This two-step control will be described using a flowchart and schematic diagrams. FIG. 6 is a flowchart for explaining the two-step control executed in the root canal treating device 100 according to the first embodiment. FIG. 7 is a schematic diagram for explaining the two-step control executed in the root canal treating device 100 according to the first embodiment. In the following flow charts and schematic diagrams, for simplification of description, a case where the root canal is cut and enlarged by driving the cutting tool 5 in the normal direction using the first cutting tool will be described.

First, the control unit 11 determines whether or not the driving start/stop button 15a has been pressed by the user to perform a driving operation (step S110). When there is no driving operation (NO in step S110), the control unit 11 returns the process to step S110 and waits for the driving operation by the user. When there is a driving operation (YES in step S110), the control unit 11 drives the cutting tool 5 in the normal direction (step S111). That is, this is the case where the cutting tool 5 is driven by the forward rotation control 111 shown in FIG. 5, and as shown in FIG. 7A, the first cutting tool 5A is attached to the head portion 2 to cut the root canal. This is the case when expanding.

The root canal length measuring circuit 12 measures the position of the tip of the cutting tool 5 in the root canal while the cutting tool 5 is driven in the normal direction. The control unit 11 determines whether or not the position of the tip of the cutting tool 5 measured by the root canal length measuring circuit 12 has reached a reference position (for example, the apex position) (step S112). When the position of the tip of the cutting tool 5 has not reached the reference position (NO in step S112), the control unit 11 returns the process to step S111 and determines whether the position of the tip of the cutting tool 5 has reached the reference position. Continue.

When the position of the tip of the cutting tool 5 reaches the reference position (YES in step S112), the control unit 11 drives the cutting tool 5 in the reverse direction (step S113). That is, this is the case where the cutting tool 5 is driven by the reverse rotation control 112 shown in FIG. 5, and as shown in FIG. 7B, the position of the tip of the first cutting tool 5A reaches the apex position, and This is the case where the cutting tool 5A is driven in reverse.

When the first cutting tool 5A is driven in reverse, the tip of the first cutting tool 5A advances in a direction in which the position of the tip of the first cutting tool 5A moves away from the apex position (Fig. 7(c)). However, when the second cutting tool 5B is erroneously attached to the head portion 2, the reverse rotation drive by the first cutting tool 5A becomes the forward rotation drive by the second cutting tool 5B, so that the direction of the apex position is increased. The tip of the second cutting tool 5B further advances (FIG. 7(f)). Originally, the drive in the reverse rotation control 112 is a drive for preventing the tip of the cutting tool 5 which has reached the reference position from further proceeding beyond the reference position. Therefore, when the cutting tool 5 is driven by the reverse rotation control 112 and the tip of the cutting tool 5 further advances in the direction of the apex position, the control unit 11 determines that the operation is not intended by the user and is an abnormal operation. ..

The control unit 11 determines the abnormal operation based on whether the position of the tip of the cutting tool 5 measured by the root canal length measuring circuit 12 has moved in the direction of the apex position (step S114). Here, the determination by the root canal length measuring circuit 12 of whether or not the position of the tip of the cutting tool 5 has moved in the direction of the root apex will be described in detail. For example, the root canal length measuring circuit 12 sets the reference position for driving the cutting tool 5 in the reverse direction to the first reference position and the position of the apex or the position from the apex side with respect to the first reference position to the second reference position. Set each as the reference position of. FIG. 8 is a schematic diagram for explaining the first reference position and the second reference position set in the root canal treating device according to the first embodiment. In FIG. 8A, in the case where the position in the root canal is displayed in a block of 20 dots in the root canal length measuring circuit 12, the first reference position is set in the block of one scale and the scale of the apex position (APEX) is set. The second reference position is set for each block. That is, the second reference position is set to the absolute position as the position of the apex. The position for setting the second reference position is not limited to the position of the apex, but may be set in the vicinity of the position of the apex (for example, the range of two blocks before and after the APEX scale). Further, in FIG. 8B, when the position within the root canal is displayed in the root canal length measuring circuit 12 by a block of 20 dots, the first reference position is set in the block of one scale from the first reference position, for example. The positions from the apical side of the three dots are set as the second reference positions. That is, the second reference position is set as a relative position with respect to the first reference position.

The control unit 11 drives the cutting tool 5 in the reverse direction by setting the first reference position and the second reference position, and the root canal length measuring circuit 12 causes the tip of the cutting tool 5 to reach the second reference position. When the arrival of the cutting tool 5 is detected, it can be determined that the root canal length measuring circuit 12 has detected the movement of the tip of the cutting tool 5 in the direction of the root apex position and the abnormal operation. That is, the control unit 11 controls the cutting tool 5 when the position of the tip of the cutting tool 5 measured in the display of the root canal length measuring circuit 12 shown in FIG. 8A reaches the first reference position from the upper side in the drawing. Is driven in reverse, and even if it is driven in reverse, when the measured tip position of the cutting tool 5 reaches the second reference position, the driving of the cutting tool 5 is stopped. The determination of whether the tip position of the cutting tool 5 has moved in the direction of the root apex by the root canal length measuring circuit 12 is not limited to the case of setting the first reference position and the second reference position. .. For example, without setting the second reference position, it may be determined whether or not the cutting tool 5 has moved from the moving direction of the position of the tip of the cutting tool 5 measured by the root canal length measuring circuit 12 toward the root apex position. ..

Returning to FIG. 8, when the position of the tip of the cutting tool 5 has not moved in the direction of the apex position (NO in step S114), the control unit 11 returns the process to step S113, and performs the reverse rotation drive by the reverse rotation control 112. Continue. When the position of the tip of the cutting tool 5 moves in the direction of the apex position (YES in step S114), the control unit 11 determines that the operation is abnormal and stops driving the cutting tool 5 as control by the fail-safe control 113. Yes (step S115). Note that the control unit 11 may perform control (reverse rotation drive in the flowchart) to reverse the driving direction of the cutting tool 5 instead of stopping the driving of the cutting tool 5 when determining that the operation is abnormal.

When it is determined that the operation is abnormal and the driving of the cutting tool 5 is stopped, the control unit 11 determines whether or not the release operation is performed by the user (step S116). When the release operation has not been performed (NO in step S116), the control unit 11 returns the process to step S116 and waits for the release operation by the user. When the release operation is performed (YES in step S116), the control unit 11 ends the driving of the cutting tool 5 in the fail-safe control 113. That is, the control unit 11 returns to the drive of the cutting tool 5 in the forward rotation control 111. When the first reference position and the second reference position are set as described above, as a releasing operation, for example, until the position of the tip of the cutting tool 5 measured by the root canal length measuring circuit 12 reaches the first reference position. An operation of moving the tip of the cutting tool 5 can be considered. The position at which the tip of the cutting tool 5 is moved by the release operation is not limited to the first reference position and may be a predetermined position that is a position closer to the crown than the apex position. In the display of the root canal length measuring circuit 12 shown in FIG. 8A, the control unit 11 changes the position of the tip of the cutting tool 5 whose driving is stopped by the fail safe control 113 from the second reference position to the first reference position. When the return releasing operation is performed, the process returns to the drive of the cutting tool 5 in the forward rotation control 111.

As described above, the root canal treating device 100 according to the first embodiment includes the drive unit configured by the micromotor 7, the motor driver 13, and the like, the control unit 11, and the root canal length measuring circuit 12. ing. The drive unit drives the cutting tool 5 held by the head unit 2 of the handpiece 1. The control unit 11 controls a drive unit that drives the cutting tool 5. The root canal length measuring circuit 12 detects the position of the tip of the cutting tool 5 in the root canal obtained by the electric root canal length measurement. The control unit 11 drives the cutting tool 5 held by the head unit 2 in the normal direction to cut the object to be cut, drives the cutting tool 5 in the normal direction, and causes the root canal length measuring circuit 12 to cut to the reference position. When the arrival of the tip of the tool 5 is detected, the cutting tool 5 is reversely driven in the reverse direction of the normal rotation driving, the cutting tool 5 is reversely driven, and the root canal length measuring circuit 12 performs cutting in the direction of the apex position. When detecting the movement of the tip of the tool 5, fail-safe control is executed.

As a result, the root canal treating device 100 according to the first embodiment controls the driving of the cutting tool 5 by the fail-safe control 113 even if the cutting tool 5 is driven by the reverse rotation control 112 to cause an unintended operation. Even if the cutting tool 5 attached to the head portion 2 is wrong, it can be safely driven.

The fail-safe control is a control for stopping the driving of the cutting tool 5, a control for reducing the rotation speed of the cutting tool 5, a control for twist driving the cutting tool 5, a control for reversing the driving direction of the cutting tool 5, and a sound output. At least one of the control, the control for outputting light, and the control for vibrating the handpiece 1 is included.

Thereby, the root canal treating device 100 according to the first embodiment can provide appropriate fail-safe control suitable for driving the cutting tool 5.

The reference position is the position preset by the user in the root canal or the position of the apex. This allows the user to arbitrarily set the position at which the cutting tool 5 is driven to be reversed by the reverse rotation control 112.

When executing the fail-safe control 113, the control unit 11 continues to execute the fail-safe control until the cancel operation is performed. As a result, the drive of the cutting tool 5 in the fail-safe control 113 is maintained until the safe drive is ensured.

The release operation is an operation in which the root canal length measuring circuit 12 detects the arrival of the tip of the cutting tool at a predetermined position which is closer to the crown than the reference position. As a result, even if the drive of the cutting tool 5 in the fail-safe control 113 is released, safe drive can be ensured.

The root canal treating device 100 further includes an informing unit 17 for informing the user. When the root canal length measuring circuit 12 detects the movement of the tip of the cutting tool 5 in the direction of the apex position, the notifying unit 17 drives the cutting tool 5 in the reverse direction and notifies the abnormality. This allows the user to recognize that an abnormal operation has occurred when the cutting tool 5 is driven by the reverse rotation control 112.

The driving method of the root canal treating device 100 includes a step of driving the cutting tool 5 held in the head portion 2 in the normal direction in the direction of cutting the object to be cut, and a normal driving of the cutting tool 5 to measure the root canal length measuring circuit. When 12 detects the arrival of the tip of the cutting tool 5 at the reference position, a step of driving the cutting tool 5 in the reverse direction of the normal rotation drive in the reverse direction, and driving the cutting tool 5 in the reverse direction, the root canal length measuring circuit 12 Detects the movement of the tip of the cutting tool 5 in the direction of the apex position, the step of executing fail-safe control is included.

As a result, in the method for driving the root canal treating device 100 according to the first embodiment, the cutting tool 5 is driven by fail-safe control even if the cutting tool 5 is driven in the reverse rotation to cause an unintended operation. Even if the cutting tool 5 attached to the head unit 2 is wrong, it can be safely driven.

(Embodiment 2)
In the root canal treating device 100 according to the first embodiment, the drive is switched to the reverse rotation control 112 and the fail safe control 113 based on the positional relationship between the position of the tip of the cutting tool 5 and the reference position. The step control was explained. However, the present invention is not limited to this, and the root canal treating device 100 switches between driving by the reverse rotation control 112 and driving by the fail-safe control 113 under conditions other than the positional relationship between the position of the tip of the cutting tool 5 and the reference position. You may perform two-step control. Two-step control executed in the root canal treating device according to the second embodiment will be described with reference to a flowchart. FIG. 9 is a flowchart for explaining the two-step control executed in the root canal treating device 100 according to the second embodiment. The root canal treating device 100 according to the second embodiment also has the same configuration as the root canal treating device 100 according to the first embodiment shown in FIGS. 1 to 3, and therefore the same reference numerals are used for the same components. The detailed description will not be repeated.

First, the control unit 11 determines whether or not the drive start/stop button 15a has been pressed by the user to perform a drive operation (step S120). When there is no driving operation (NO in step S120), the control unit 11 returns the process to step S120 and waits for the driving operation by the user. If there is a driving operation (YES in step S120), the control unit 11 drives the cutting tool 5 in the normal direction to rotate normally (step S121). That is, this is the case where the cutting tool 5 is driven by the forward rotation control 111 shown in FIG.

The load detection unit determines whether the load applied to the cutting tool 5 has become the reference load (step S122). That is, when the load applied to the cutting tool 5 becomes the reference load, the control unit 11 switches from driving in the forward rotation control 111 to driving in the reverse rotation control 112 in order to prevent breakage of the cutting tool 5. When the load applied to the cutting tool 5 is smaller than the reference load (NO in step S122), the control unit 11 returns the process to step S121 and continues to determine whether the load applied to the cutting tool 5 has become the reference load.

If the load applied to the cutting tool 5 has become the reference load (YES in step S122), the control unit 11 drives the cutting tool 5 in reverse by a reverse operation (step S123). That is, this is the case where the cutting tool 5 is driven by the reverse rotation control 112 shown in FIG.

When the first cutting tool 5A is driven in the reverse direction, the first cutting tool 5A is rotated in the non-cutting direction, so that the blade of the cutting tool 5 biting into the root canal wall is released, and the load applied to the first cutting tool 5A is small. Become. However, when the second cutting tool 5B is erroneously attached to the head portion 2, the reverse rotation drive of the first cutting tool 5A becomes the forward rotation drive of the second cutting tool 5B. The blade of the cutting tool 5 that is rotated in the cutting direction and bites into the root canal wall further bites, and the load applied to the second cutting tool 5B increases. Originally, the drive in the reverse rotation control 112 is a drive for preventing the breakage of the cutting tool 5 by driving the load applied to the cutting tool 5 to be smaller than the reference load. Therefore, when the cutting tool 5 is driven by the reverse rotation control 112 and the load applied to the cutting tool 5 becomes larger than the reference load, the control unit 11 determines that the operation is not intended by the user and is an abnormal operation.

The control unit 11 determines whether or not the load applied to the cutting tool 5 by the load detection unit is larger than the reference load by determining the abnormal operation (step S124). When the load applied to the cutting tool 5 becomes smaller than the reference load (NO in step S124), the control unit 11 returns the process to step S123 and continues the reverse rotation drive by the reverse rotation control 112. When the load applied to the cutting tool 5 becomes larger than the reference load (YES in step S124), the control unit 11 determines that the operation is abnormal and stops the driving of the cutting tool 5 as the control of the fail safe control 113 (step). S125). Note that the control unit 11 may perform control (reverse rotation drive in the flowchart) to reverse the driving direction of the cutting tool 5 instead of stopping the driving of the cutting tool 5 when determining that the operation is abnormal.

When it is determined that the operation is abnormal and the driving of the cutting tool 5 is stopped, the control unit 11 determines whether or not the release operation is performed by the user (step S126). When the release operation has not been performed (NO in step S126), the control unit 11 returns the process to step S126 and waits for the release operation by the user. When the release operation is performed (YES in step S126), the control unit 11 ends the driving of the cutting tool 5 in the fail-safe control 113. That is, the control unit 11 returns to the drive of the cutting tool 5 in the forward rotation control 111.

As described above, the root canal treating device 100 according to the second embodiment includes the drive unit including the micromotor 7 and the motor driver 13, the control unit 11, and the load detecting unit. The drive unit drives the cutting tool 5 held by the head unit 2 of the handpiece 1. The control unit 11 controls a drive unit that drives the cutting tool 5. The load detector detects the load applied to the cutting tool 5. The control unit 11 drives the cutting tool 5 held by the head unit 2 in the normal rotation direction to cut an object to be cut, drives the cutting tool 5 in the normal rotation direction, and applies a load to the cutting tool 5 detected by the load detection unit. Is equal to or greater than the reference load, the cutting tool 5 is reversely driven in the reverse direction of the normal rotation drive, the cutting tool 5 is reversely driven, and the load applied to the cutting tool 5 detected by the load detection unit does not become less than the reference load. If so, execute fail-safe control.

As a result, in the root canal treating device 100 according to the second embodiment, the drive of the cutting tool 5 is controlled by the fail-safe control 113 even if the reverse rotation control 112 drives the cutting tool 5 to cause an unintended operation. Even if the cutting tool 5 attached to the head portion 2 is wrong, it can be safely driven.

Based on the magnitude relationship between the load applied to the cutting tool 5 and the reference load described in the second embodiment, the configuration of the two-step control for switching to the reverse rotation control 112 and the fail-safe control 113 is the root according to the first embodiment. You may combine with the structure of the two-step control based on the relationship with the reference position in the tube treatment device 100. In addition, if only the root canal treating device 100 according to the second embodiment is configured, it is a root canal treating device that does not include a root canal length measuring system and can detect the load of the cutting tool 5 and only expands the canal. It may be.

(Modification)
(1) In the root canal treating device 100 according to the first and second embodiments, the configuration in which the motor unit 6 and the control box 9 are built in is a cordless type root canal treating device, but the invention is not limited to this. Instead, the handpiece 1 may be connected to the control box 9 provided outside through the hose 61. FIG. 10 is a schematic diagram showing a configuration of a root canal treating device 100a connected to a control box 9 provided outside the handpiece 1 by a cord. In the configuration of the root canal treating device 100a, the same components as those shown in FIGS. 1 to 3 are designated by the same reference numerals and detailed description thereof will not be repeated.

A root canal treating device 100a shown in FIG. 10 includes a handpiece 1 for dental root canal treatment, a motor unit 6, and a control box 9. In the handpiece 1 for dental root canal treatment, a motor unit 6 for rotationally driving a cutting tool 5 (file or reamer) held by the head 2 is detachably connected to the base of the grip 4. It The dental instrument 10 is configured with the motor unit 6 connected to the handpiece 1.

The motor unit 6 has a micromotor 7 built-in, and a hose having a power supply lead wire 71 for supplying power to the micromotor 7, a signal lead wire 8 for transmitting a signal to the root canal length measuring circuit 12, and the like. It is connected to the control box 9 via 61.

As shown in FIG. 10, the control box 9 has a holder 10a attached to the side of the main body for holding the instrument 10 when not in use. Further, in the control box 9, a foot controller 18 is connected to the control unit 11, and a lead wire 19 is connected to the root canal length measuring circuit 12. Although the lead wire 19 is drawn from the control box 9, it may be drawn so as to be branched from the middle of the hose 61.

The setting unit 14 has a selection button 15b for changing the setting on the surface of the control box 9, and controls the rotation direction, rotation speed, rotation angle, etc. of the cutting tool 5 by operating the selection button 15b. Set the standard.

The operation unit 15 has a drive start/stop button 15a on the surface of the control box 9, and the drive of the cutting tool 5 can be started or stopped by operating the drive start/stop button 15a.

The foot controller 18 is an operation reception unit that controls the driving of the cutting tool 5 by the micromotor 7 by stepping. The drive control of the cutting tool 5 by the micromotor 7 is not limited to the foot controller 18, but an operation switch (not shown) is provided in the grip portion 4 of the handpiece 1, and the operation switch and the foot controller 18 are provided. You may make it drive-control the cutting tool 5 using together and. Further, for example, while the foot controller 18 is being operated on by the foot, the root canal length measuring circuit 12 detects that the cutting tool 5 has been inserted into the root canal, so that the cutting tool 5 is rotated. You may make it start.

In addition, although the control box 9 of the root canal treating device 100a has been described as being placed on a tray table or a side table installed on the side of the dental examination table and used, the present invention is not limited to this. The control box 9 may be incorporated in the tray table or the side table.

(2) In the root canal treating device 100 according to the first and second embodiments, the case where the micromotor 7 is used as the power source for driving the cutting tool 5 has been described, but the present invention is not limited to this, and an air motor or the like may be used. It may be another drive source.

The embodiments disclosed this time are to be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

1 handpiece, 2 head part, 3 neck part, 4 gripping part, 5 cutting tool, 6 motor unit, 7 micromotor, 8 signal lead wire, 9 control box, 10 instruments, 10a holder, 11 control part, 12 root canal length measurement circuit, 13 motor driver, 13a transistor switch, 13b transistor driver circuit, 13c rotation direction change switch, 13d load detection resistor, 14 setting unit, 14a, 14b, 14c variable resistor, 15 operation unit, 15a drive Start/stop button, 15b selection button, 16 display section, 17 notification section, 18 foot controller, 19 lead wire, 19a oral electrode, 100 root canal treatment device, 110 comparison circuit.

Claims

A drive unit that drives the cutting tool held on the head of the handpiece,
A control unit that controls the drive unit that drives the cutting tool;
A position detection unit for detecting the position in the root canal of the tip of the cutting tool obtained by electrical root canal length measurement,
The control unit is
The cutting tool held in the head portion is driven in the normal direction in the direction of cutting the object to be cut,
When the cutting tool is driven in the normal direction and the position detection unit detects the arrival of the tip of the cutting tool to a reference position, the cutting tool is reversely driven in the reverse direction of the normal rotation driving,
The dental treatment apparatus which performs fail-safe control when the cutting tool is driven in the reverse direction to detect the movement of the tip of the cutting tool in the direction of the apex position by the position detection unit.
The fail-safe control is a control for stopping the driving of the cutting tool, a control for reducing the rotation speed of the cutting tool, a control for twist driving the cutting tool, a control for reversing the driving direction of the cutting tool, and outputting a sound. The dental treatment apparatus according to claim 1, further comprising at least one of a control for turning on, a control for outputting light, and a control for vibrating the handpiece.
The dental treatment device according to claim 1 or 2, wherein the reference position is a position preset by a user in the root canal or a position of a root apex.
The position detection unit sets the reference position for driving the cutting tool in the reverse direction to a first reference position, the position of the apex, or the position from the apex side with respect to the first reference position to the second reference position. Set each with the reference position,
When the control unit reversely drives the cutting tool and the position detection unit detects arrival of the tip of the cutting tool to the second reference position, the position detection unit detects the apex position. The dental treatment apparatus according to claim 1 or 2, wherein the fail-safe control is executed on the assumption that the movement of the tip of the cutting tool in the direction is detected.
The dental treatment device according to any one of claims 1 to 4, wherein, when the control unit executes the fail-safe control, the control unit continues the execution of the fail-safe control until a release operation is performed.
The dental treatment device according to claim 5, wherein the releasing operation is an operation of detecting arrival of the tip of the cutting tool to a predetermined position which is closer to the crown than the apex position.
Further comprising an informing unit for informing the user,
The reporting unit reports the abnormality when the cutting tool is driven in the reverse direction and the position detection unit detects the movement of the tip of the cutting tool in the direction of the root apex. The dental treatment device according to any one of 6 above.
Further comprising a load detection unit for detecting a load applied to the cutting tool,
When the cutting tool is driven in the normal direction and the load applied to the cutting tool detected by the load detection unit is equal to or higher than a reference load, the cutting tool is reversely driven in the reverse direction of the normal rotation driving,
8. The fail-safe control is executed when the load applied to the cutting tool detected by the load detection unit is not less than the reference load by driving the cutting tool in the reverse direction. The dental treatment apparatus according to item 1.
A drive unit that drives the cutting tool held on the head of the handpiece,
A control unit that controls the drive unit that drives the cutting tool;
A load detection unit for detecting a load applied to the cutting tool,
The control unit is
The cutting tool held in the head portion is driven in the normal direction in the direction of cutting the object to be cut,
When the cutting tool is driven in the normal direction and the load applied to the cutting tool detected by the load detection unit is equal to or higher than a reference load, the cutting tool is reversely driven in the reverse direction of the normal rotation driving,
A dental treatment device that performs fail-safe control when the cutting tool is driven in the reverse direction and the load applied to the cutting tool detected by the load detection unit does not fall below the reference load.
A drive unit that drives the cutting tool held by the head of the handpiece, a control unit that controls the drive unit that drives the cutting tool, and a root of the tip of the cutting tool obtained by electrical root canal length measurement. A method for driving a dental treatment apparatus comprising a position detecting section for detecting a position in a tube,
The control unit is
A step in which the cutting tool held in the head section is driven in the normal direction in a direction of cutting a cutting object;
When driving the cutting tool in the normal rotation, when the position detection unit detects the arrival of the tip of the cutting tool to a reference position, driving the cutting tool in the reverse direction of the normal rotation driving, reverse driving,
When the cutting tool is driven in the reverse direction and the position detection unit detects movement of the tip of the cutting tool in the direction of the apex position, a step of executing fail-safe control is included. Driving method.